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Back To Static!

We had a long discussion on the possible causes of static electrical charges on records in another thread. We just had a real good cold snap in New England dropping the humidity to under 20% so I was able to run a set of qualitative experiments documenting some surprising results that I hope will clear up a lot of the mystery and help people contro static charge and the accumulation of dust on their record. 
Static field meters are expensive.  The cheapest one I could find cost $260. I had to find a more sensitive way to measure static as it became apparent that using your own hair is very insensitive. Studying the Triboelectric series I noted that polypropylene is at the opposite end to PVS.  I have polypropylene in the form of suture material, the blue thread that many of you have seen. I tied a length of 6-0 Prolene  to a wood dowel and it worked beautifully. The PVC attracts it like a magnet and the Label repels it. It will pick up very small charges that otherwise go undetected. I can now define four conditions; No charge, Light charge, Charged and Heavily charged. It turns out that completely discharging a record is not easy. The label will actually donate electrons to the vinyl over time reaching an equilibrium point. Totally discharging a record required using a Pro-Ject conductive record brush wired to ground. If I suspend a discharged record (no thread activity) by it's hole within 30 minutes it will develop a slight charge (vinyl attracts the thread, label repels it). This will appear to us as an uncharged record. 
Does playing a record increase the static charge?  Yes absolutely, and the charge is additive. Playing the record over and over again progressively increases the charge from slightly to heavily charged. 
Does how you store the record effect charge? Yes absolutely. Records stored in MoFi antistatic sleeves come out with the baseline small charge. Records stored in paper come out with a noticeably higher charge. These are records that have been totally discharged prior to storage. A record that is charged when you put it away will come out at least as charged even if you are using anti static sleeves. Do conductive sweep arms work? Sort of. If the sweep arm leads the stylus charge will still accumulate. The brush has to track with the stylus. 
Unfortunately, I could not get hold of a Zerostat to test it's effectiveness. Regardless, a charge will accumulate with play.
The single best way to totally discharge a record is a conductive brush wired to ground. Just holding it will not work as well. The impedance of your tissue is in the megaohms. You want a dead short. Even so, a small charge will accumulate over a short period of time. The safest assumption is that there is always a charge on the record attracting dust. So, don't leave records out for any period of time. In regards to the hot topic of dust covers, a properly designed Dust cover does not affect sound quality. If your dust cover does effect sound quality in a negative way then you have a choice between sound quality and dirtier records. Your records, your choice. 
I would love to be able to stage voltages. If in the future I manage to come up with a static field meter I will repeat all of this in a quantitative way. Humidity is a huge factor. Those living in more humid environments have less trouble with static accumulation. I suspect everything occurs in like fashion just the voltages are lower. Lower to the point that they do not need any device to lower the charge?  I don't know. 

128x128mijostyn
mijostyn's avatar
mijostyn OP
8,570 posts
 
@dover , I use these https://www.sleevecityusa.com/diskeeper-audiophile-inner-sleeve-50-pack-p/312nrps.htm
I believe these are the same sleeves antinn refers to above. They are suspiciously like the MF sleeves. I have had no problems with them. They are sturdy and slip into the cover nicely without crimping or folding. Anti static sleeves is a misnomer. They do not remove static, they just will not donate electrons to PVC. If you put a charged record into any of these sleeves you will get the same charge when you pull the record back out. The record has to be discharged by some method. Even a very slight charge on the record will collect dust and all you have to do is look at a record funny and it will collect a charge. The reason that paper is so bad is that it loves to donate electrons to PVC. Shows you how cheap the record companies could be! Classical records like Decca, London, DGG, Erato and many others always used appropriate plastic sleeves. But, popular music, paper. It seems in the eyes of the record companies popular and jazz music lovers are second class citizens.

You can make a very sensitive qualitative static measuring device by tying some wool thread to the end of a wooden skewer leaving about 2 inches hanging. Negative charging will pull the thread towards the charge. Positive charging will repulse the thread. Wool is at the opposite end of the triboelectric series. It is very good at donating electrons and will maintain a positive charge. You can get a feel for how strong the charge is. The thread will pick up very low charges, charges that you would otherwise not know existed. 

Just playing a record in low humidity conditions will create a small charge on the record. Whether or not this is the stylus doing this is open for debate. The charge is so small you would not notice it. But, the effect is cumulative. Playing the record several times will add enough charge that it will become noticeable. This effect essentially does not happen in humidity's over 30%.  
atmasphere's avatar
atmasphere
11,948 posts
 
@mijostyn  I've used a carbon fiber dust brush that is tied to my grounded steel equipment stand via a wire riveted to the brush. I can't say how effective it really is but I don't get pops and noise from static.

But it occurs to me that if I can get the charge down lower on the LP when its spinning, I might free more dust when using the brush. Sounds like if a grounded metal bar were simply suspended over the playing surface maybe 1/4" or so above it that it might be able to remove a significant amount of charge?


mijostyn's avatar
mijostyn OP
8,570 posts
 
Very interesting idea. antinn and I were reviewing a paper he found comparing the effectiveness of a grounded brush vs ionization vs both together in neutralizing static on plastic film. The brush was not touching the film but 1/16th of an inch off. It did lower the charge but it was not as effective as ionization. However they worked best together. So, a grounded metal bar or rod suspended over the record will work but it would have to be very close, so close that the slightest warp would stop the entire show. 

What you are doing with your grounded brush is fine. I recommend wiring these brushes to ground all the time as just holding them does not do much good. The thing is you do not want to use it on a spinning record. Move the record under the brush by hand slowly. None of these brushes will get deep down into the groove. They will only remove surface dust. If the record starts out clean and your record hygiene and environment are good this should be all you need to do.
dover
2,262 posts
 
@mijostyn
I believe these are the same sleeves antinn refers to above. They are suspiciously like the MF sleeves. I have had no problems with them. They are sturdy and slip into the cover nicely without crimping or folding. Anti static sleeves is a misnomer. They do not remove static, they just will not donate electrons to PVC. If you put a charged record into any of these sleeves you will get the same charge when you pull the record back out. The record has to be discharged by some method. Even a very slight charge on the record will collect dust and all you have to do is look at a record funny and it will collect a charge. 
Yes, Analog Relax rscommend using their brush after playing and before you put the record back in its sleeve to discharge the record before storing.


antinn
408 posts
 
@mijostyn,

 None of these brushes will get deep down into the groove.

Here is the approximate diameter of the three conductive bristle materials used for records:  For reference the V-shaped groove has ‘nominal’ dimensions of 56 microns (0.0022") wide at the top, a radius of 6 microns (0.00025") at the bottom, and a ‘nominal’ depth of 28 microns (0.0011").

Carbon Fiber:  0.00028" (~7 microns).  This can penetrate deeply into the groove almost to the very bottom.

COREBRID™ B (Analog Reflex):  0.0012” (~30 microns).  This can penetrate only partially into the groove. 

THUNDERON: 0.0028" (~70 microns).  This will not penetrate the groove.
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